Protein Adsorption Dynamics at Liquid-Solid Interfaces

Protein adsorption at liquid–solid interfaces underpins a vast array of natural and engineered systems, from blood–biomaterial interactions to environmental remediation technologies. The process is governed by a balance of electrostatic, hydrophobic and van der Waals forces, and is strongly influenced by solution conditions such as pH, ionic strength and protein concentration. On approaching a surface, proteins may undergo conformational rearrangements that affect layer structure, water content and mechanical properties. Adsorption kinetics determine how rapidly a surface becomes passivated or functionalised, while competition between adsorption and desorption dictates long-term stability. Advances in experimental and computational techniques have revealed how surface chemistry, topography and nanostructure direct protein orientation, packing density and multilayer formation. Insight into these dynamics is critical for the rational design of antifouling coatings, biosensors, drug-delivery vehicles and catalytic interfaces, as well as for understanding protein behaviour in geological and aquatic environments.

Research from Nature Portfolio

Studies have shown that the conformational flexibility of bovine serum albumin (BSA) depends on the presence of fatty acid stabilisers acquired during purification. Fatty acid-free BSA exhibits reduced charge repulsion and greater structural adaptability, forming more rigidly attached, tightly packed films that deliver superior antifouling performance on both planar surfaces and nanoparticle substrates. In silico advances have refined the Random Sequential Adsorption model to incorporate nanostructured geometries, revealing that convex features lower steric hindrance and promote higher coverage when protein size aligns with surface topography. Application of this model to human serum albumin on nanostructured black silicon surfaces has allowed quantification of the blocking function and occupancy-dependent adsorption probability. In another investigation, in-situ attenuated total reflection FTIR combined with two-dimensional correlation spectroscopy has elucidated BSA structural evolution on hematite under varying pH and ionic strength. Protein secondary structure shifts from α-helix to β-sheet during adsorption, adsorption peaks near the isoelectric point and elevated ionic strength diminishes overall uptake, while higher loadings encourage protein–protein interactions and multilayer assembly.

Research from all publishers

Work on pH-responsive BSA hydrogel nanolayers at the gold–liquid interface has demonstrated reversible water uptake and release during saline rinsing cycles. Quartz crystal microbalance with dissipation, atomic force microscopy and contact-angle measurements reveal that while the protein film remains irreversibly bound, its thickness and hydration state can be tuned by alternating between pH 7.0 and pH 4.5, pointing towards applications in smart diagnostics and drug-delivery platforms. In studies of protein adsorption onto silica nanoparticles, lysozyme and β-lactoglobulin exhibit a sharp increase in adsorbed amount near their respective isoelectric points, with electrolyte screening modulating both protein–surface and protein–protein attractions. Analysis via a two-state Guggenheim–Anderson–De Boer model distinguishes strongly and weakly bound populations. Investigations of BSA binding to self-assembled monolayers using combinatorial quartz crystal microbalance with dissipation and spectroscopic ellipsometry show that charged surfaces enhance layer density and thickness, that adsorption scales with protein concentration and neutral pH, and that lowering the pH below the isoelectric point triggers partial desorption.

Protein Adsorption Dynamics at Liquid-Solid Interfaces publication trend

The graph below shows the total number of articles in protein adsorption dynamics at liquid-solid interfaces across all publications each year (not limited to Nature Index journals).

Technical terms

Liquid–solid interface: The boundary region where a liquid phase meets a solid substrate, critical for interfacial protein interactions.

Adsorption kinetics: The rate and mechanism by which proteins adhere to and detach from surfaces over time.

Isoelectric point: The pH at which a protein carries no net electrical charge, influencing its affinity for charged surfaces.

Quartz crystal microbalance with dissipation (QCM-D): A sensor technique measuring mass changes and viscoelastic properties of adsorbed films in real time.

Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopy: A method for probing interfacial molecular structures by analysing infrared absorption spectra.

Two-dimensional correlation spectroscopy (2D-COS): A data-analysis technique that reveals sequential molecular changes during spectroscopic measurements.

References

1. Conformational flexibility of fatty acid-free bovine serum albumin proteins enables superior antifouling coatings. Communications Materials (2020).
2. Simulations of Protein Adsorption on Nanostructured Surfaces. Scientific Reports (2019).
3. The molecular insights into protein adsorption on hematite surface disclosed by in-situ ATR-FTIR/2D-COS study. Scientific Reports (2020).
4. Reversible pH Responsive Bovine Serum Albumin Hydrogel Sponge Nanolayer. Frontiers in Bioengineering and Biotechnology (2020).
5. Characterization of protein adsorption onto silica nanoparticles: influence of pH and ionic strength. Colloid and Polymer Science (2015).
6. Investigation of Bovine Serum Albumin (BSA) Attachment onto Self-Assembled Monolayers (SAMs) Using Combinatorial Quartz Crystal Microbalance with Dissipation (QCM-D) and Spectroscopic Ellipsometry (SE). PLOS ONE (2015).